class_docstr: Barrier(wires)
  The Barrier operator, used to separate the compilation process into blocks or as a visual tool.
  
  **Details:**
  
  * Number of wires: AnyWires
  * Number of parameters: 0
  
  Args:
      only_visual (bool): True if we do not want it to have an impact on the compilation process. Default is False.
      wires (Sequence[int] or int): the wires the operation acts on
code: def _controlled(self, _):
      return copy(self).queue()
  
imports: from copy import copy
  import pennylane
  from pennylane.operation import AnyWires, Operation
  from pennylane.wires import Wires
label_desc: Use image node_id 4 for calling the Barrier obj's underlying member method code with example usage: obj._controlled(_) and returns: copy